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        <span>88</span>
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    <script>

        // 判断一些在正则中有特殊含义的符号的时候,需要用到转义   \

        //    []   /   {}   ?   +   *


        // 检验  /
        let reg = /\// ;
        console.log(reg.test('///'))


        // 校验  [

        let reg2 = /\[/ ;

        

    </script>
    
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